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31.
OBJECTIVES: The primary objective of the IDEAL study is to determine whether the timing of dialysis initiation has an effect on survival in subjects with end-stage renal disease (ESRD). The secondary objectives are to determine the impact of "early start" versus "late start" dialysis on nutritional and cardiac morbidity, quality of life, and economic cost. DESIGN: Prospective multicenter randomized controlled trial. Patients are randomized to commence dialysis at a glomerular filtration rate (by Cockcroft-Gault) of either 10-14 mL/minute/1.73 m2 ("early start") or 5-7 mL/min/1.73 m2 ("late start"), with stratification for dialysis modality (hemodialysis vs peritoneal dialysis), study center, and the presence or not of diabetes mellitus. SETTING: Dialysis units throughout Australia and New Zealand. PATIENTS: Patients with ESRD commencing chronic dialysis therapy. OUTCOME MEASURES: Three years from randomization, all-cause mortality, morbidity, and economic impact; structural and functional cardiac status, nutritional state, and quality of life will be assessed. RESULTS: To date, 388 patients of a minimum 800 patients have been entered and randomized into the study. Current recruitment rates suggest sufficient patients will be enrolled by December 2004 and follow-up completed by December 2007. CONCLUSIONS: The IDEAL study will provide evidence for the optimal time to commence dialysis.  相似文献   
32.
Mothers breast feeding 2 weeks after delivery were studied. One group (106 mothers) were advised to 'eat for two' during lactation to sustain their milk supply. They were compared at 3 months with a control group of 152 mothers. At 3 months only half as many advised group mothers had weaned their babies due to insufficient milk as control mothers. The numbers weaning for other reasons were similar in both groups. More breast feeding mothers reported an increased appetite during lactation than did mothers who had changed to artificial feeding. Smokers were more likely to have given up breast feeding between 2 weeks and 3 months than non-smokers but smoking was not associated with any particular weaning reason. Women taking a contraceptive pill during lactation more often experienced a diminution of milk supply than non-pill-takers. Sustained lactation benefits the mother since those who were still breast feeding were less likely to suffer from depression or fatigue at 3 months, and were more likely to have lost weight. The early introduction of solids was less frequent among infants being breast fed at 3 months.  相似文献   
33.
Nurse education is established in higher education but nurse academics remain concerned about nursing's lack of equal status within the academy. This paper reports findings of a small study of nurse lecturers' views which support other published studies. It argues that cultural factors which contribute to nursing's problems gaining equal status include anti-intellectualism within nursing and academic denigration of practice. These cultural factors are linked to the history of women in higher education, the separation between intellectual education and practical, skill-based training, the low status of caring courses and the resulting mutual denigration of culturally opposed groups. Anti-intellectualism in nursing can be seen as a defensive reaction against an academic culture that defines practical activity as inferior to abstract thinking skills. This can lead to limited educational opportunities to examine the structural and cultural context of nursing. In Freire's view, this is a necessary part of education for freedom. Current cultural change, in nursing and higher education, including an emphasis on learning outcomes and transferable skills, provides new opportunities for nursing to contribute to educational change. Removing cultural barriers to the educated nurse is a responsibility shared by universities and by the nursing profession.  相似文献   
34.
Xen2174 is a structural analogue of Mr1A, a chi-conopeptide recently isolated from the venom of the marine cone snail, Conus marmoreus. Although both chi-conopeptides are highly selective inhibitors of the norepinephrine transporter (NET), Xen2174 has superior chemical stability relative to Mr1A. It is well-known that tricyclic antidepressants (TCAs) are also potent NET inhibitors, but their poor selectivity relative to other monoamine transporters and various G-protein-coupled receptors, results in dose-limiting side-effects in vivo. As TCAs and the alpha(2)-adrenoceptor agonist, clonidine, have established efficacy for the relief of neuropathic pain, this study examined whether intrathecal (i.t.) Xen2174 alleviated mechanical allodynia in rats with either a chronic constriction injury of the sciatic nerve (CCI-rats) or an L5/L6 spinal-nerve injury. The anti-allodynic responses of i.t. Mr1A and i.t. morphine were also investigated in CCI-rats. Paw withdrawal thresholds were assessed using calibrated von Frey filaments. Bolus doses of i.t. Xen2174 produced dose-dependent relief of mechanical allodynia in CCI-rats and in spinal nerve-ligated rats. Dose-dependent anti-allodynic effects were also produced by i.t. bolus doses of Mr1A and morphine in CCI-rats, but a pronounced 'ceiling' effect was observed for i.t. morphine. The side-effect profiles were mild for both chi-conopeptides with an absence of sedation. Confirming the noradrenergic mechanism of action, i.t. co-administration of yohimbine (100 nmol) with Xen2174 (10 nmol) abolished Xen2174s anti-allodynic actions. Xen2174 appears to be a promising candidate for development as a novel therapeutic for i.t. administration to patients with persistent neuropathic pain.  相似文献   
35.
PURPOSE: To describe the use of a clinical decision-making work sheet as a tool to teach communication skills to advanced practice nurse (APN) students. Achievement of competencies in communication and documentation that utilize language and communication strategies that are shared with other health professionals promotes effective collaborative practice among members of the multidisciplinary provider team. DATA SOURCES: Review of the recent Institute of Medicine report on health professions education and other health professional literature. CONCLUSIONS: The Clinical Decision-Making Work Sheet helps APN students effectively communicate in real-world clinical settings. The clinical work sheet allows nurse practitioner students to communicate more effectively and efficiently, using a vocabulary that is shared with other members of the multidisciplinary health care provider team. Use of the tool in students' clinical-rotation settings facilitates effective application and refinement of the clinical decision-making skills that students learned in the advanced health assessment course. IMPLICATIONS FOR PRACTICE: Faculty have the responsibility to assist nurses as they transition from traditional nursing to APN roles. The work sheet facilitates learning the common language for data collection, clinical decision making, documentation, and reporting that is shared with other health professionals. Using the tool, students learn to efficiently organize information that supports communication and documentation that enhances their clinical problem-solving skills. Case presentation and documentation using the work sheet provide a basis for preceptor and student interaction and for student evaluation.  相似文献   
36.
Complex simulations can facilitate students' synthesis of knowledge. Simulations of cognitively impaired elders provide nursing students the opportunity to use critical thinking and clinical decision-making skills in complex patient care situations. The authors report their experiences in designing, implementing, and evaluating a simulation on cognitive problems in elders using actors. This simulation required third-year baccalaureate nursing students to differentiate delirium from dementia, identify symptoms of heart failure, and address a family member's concerns.  相似文献   
37.
BACKGROUND: Septic shock is characterized by arteriolar vasodilation and hypotension. We have tested the hypothesis that nitric oxide arising from inducible nitric oxide synthase in the central nervous system is responsible for the deficiency in vasopressin release and consequent hypotension during experimental septic shock. METHODS AND RESULTS: Septic shock was induced in male Wistar rats by intravenous injection of 1.5 mg/kg lipopolysaccharide. After lipopolysaccharide administration, we found a significant decrease in mean arterial pressure with a concomitant increase in heart rate, a significant decrease in diuresis, and a transitory decrease in body temperature. An increase in plasma vasopressin concentrations occurred in these animals and was present for 2 hrs after lipopolysaccharide administration, returning close to basal concentrations thereafter and remaining unchanged for the next 24 hrs. When lipopolysaccharide was combined with central administration of aminoguanidine, an inducible nitric oxide synthase inhibitor, we observed a sustained increase in plasma vasopressin concentration and in the maintenance of blood pressure at 4 and 6 hrs after lipopolysaccharide treatment compared with rats treated with lipopolysaccharide alone. CONCLUSION: These data indicate that central nitric oxide arising from the inducible nitric oxide synthase pathway plays an important inhibitory role in vasopressin release during experimental septic shock and may be responsible for the hypotension occurring in this vasodilatory shock.  相似文献   
38.
39.
BACKGROUND: Cell-free fetal DNA circulating in maternal blood has potential as a safer alternative to invasive methods of prenatal testing for paternally inherited genetic alterations, such as cystic fibrosis (CF) mutations. METHODS: We used allele-specific PCR to detect mutated CF D1152H DNA in the presence of an excess of the corresponding wild-type sequence. Pfx buffer (Invitrogen) containing replication accessory proteins and Taq polymerase with no proofreading activity was combined with TaqMaster PCR Enhancer (Eppendorf) to suppress nonspecific amplification of the wild-type allele. The procedure was tested on DNA isolated from plasma drawn from 11 pregnant women (gestational age, 11-19.2 weeks), with mutation confirmation by chorionic villus sampling. RESULTS: The method detected 5 copies of the CF D1152H mutant allele in the presence of up to approximately 100,000 copies of wild-type allele without interference from the wild-type sequence. The D1152H mutation was correctly identified in one positive sample; the only false-positive result was seen in a mishandled sample. CONCLUSIONS: This procedure allows for reliable detection of the paternally inherited D1152H mutation and has potential application for detection of other mutations, which may help reduce the need for invasive testing.  相似文献   
40.
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